1. Field of the Invention
The present invention generally relates to the field of reflective optical systems and, more particularly, to the design and fabrication of mirror systems used for projecting one or more optical images from one location to another, such as in a kaleidoscope.
2. The Prior Art
Reflective optical systems such as those comprising an arrangement of several mirrors for the purpose of projecting one or more images from one location to another are typically constructed using a precise level base plate as the starting structural component. Mirror holders and supports are then precisely laid out on this base plate according to the optical design of the reflective system.
The level of cost and precision for the design and construction for reflective optical systems or mirror systems attainable by such a method is generally directly proportional to the amount of efforts devoted to such tasks. For applications where cost, precision and size are of paramount importance for such reflective optical systems, the general design and construction for them as referred to above are grossly insufficient. The need for an entirely new approach for addressing this problem, taking advantage of concomitantly developed technologies over the past few decades such as the evolution of the so-called "micro-chip" in the semiconductor industry and the like, is apparent.
One interesting and relevant example illustrating this can be found in the kaleidoscope mirror arrangements. There are two basic systems of mirrors in kaleidoscopes: the two-mirror system which produces one central image and the three-mirror which produces images reflected throughout the entire field of view. Both are set up in a triangular configuration in a tube similar to a prism. In the two-mirror system, the two mirrors are arranged in a "V" with the third side of the triangle a blackened, non-reflective surface. The angle of the "V" determines the number of reflections contributing to the overall intricacy of the central pattern. The three-mirror system reacts similarly to the two-mirror system with one major exception. A third mirror replaces the blackened side of the triangle in the two-mirror system and produces a continuation of reflections throughout the entire field of view. Symmetrical images are much harder to achieve in a three-mirror system because now there are three angles which must be accurate instead of only one angle in the two-mirror design. The most common and simplest arrangement for the 3-mirror system is the 60.degree.-60.degree.-60.degree. equilateral triangle. Here each angle produces 6-fold patterns which results in a design of continuous triangles.
Oddly, the construction of the kaleidoscope mirror arrangements, two of the most common ones as described above, has not changed since the invention of this wonderful device by Sir David Brewster in 1816. Mirror systems entail choice of material, dimension, angles and configuration, and they are the soul of the kaleidoscope. However, even though the design for the mirror systems has gone through many changes since the invention of the kaleidoscope, the manner in which the mirror systems are put together remain virtually unchanged.
The first surface mirrors (as versus second surface mirrors for better overall optical quality of the images) are first cut into the correct sizes and then they are manually glued or soldered together along the axial or long edges of the mirrors, with or without the use of a fixture or tooling. In order to achieve just a reasonably acceptable optical precision for such mirror systems, tooling fixtures must be used unless it is being handled by a skillful artisan who has had many years of practice in the art. But even then the optical precision of such mirror systems is very much limited to probably no more than a few thousandths of an inch. For those mirror systems that are put together without tooling fixtures, the optical precision will indeed be very marginal, leading to rather poor or "amateurish" image quality.
The use of manual labor to construct kaleidoscope mirror systems without relying on tooling fixtures generally not only leads to poor optical precision, but also much increased costs due to the amount of time needed for such an assembly. Even with the help of tooling fixtures, the assembly time is not much reduced unless the assembly is automated, which could add significant unwanted capital expenditure. Thus at least from the cost standpoint, there exists a need for an improved methodology for fabricating such mirror systems for kaleidoscopes.
Another major drawback for not attaining high optical precision for such mirror systems, when manual labor without tooling fixtures is used, is the limitation on the size reduction for such systems. For large mirror systems, poor optical precision in their assembly might still lead to acceptable performance from the standpoint of image quality. However, when the size of the mirror systems starts to come down, for example by an order of magnitude, then the same optical imprecision could lead to totally unacceptable image quality. This is another reason why an improved methodology for fabricating such mirror systems is highly desirable.
As mentioned above, the most common mirror systems for kaleidoscopes are the two-mirror and three-mirror systems which comprise basically three optical elements (two mirrors and a non-reflective element for the two-mirror system, and three mirrors for the three-mirror system) set up in a triangular configuration--in a tube similar to a hollow prism. Other more complicated mirror systems are also possible in theory, such as the square, rectangular, and large multiples of mirrors or n-mirror systems, where n is greater than three. Tapered mirrors of three or more sides are also possible. Even combined mirror systems such as two separate but adjoined mirror systems within a kaleidoscope, each with its own eye-piece and view point of the object chamber, are possible. The main reason why these more complicated mirror systems are seldom used and seen in kaleidoscopes is that the currently prevalent manual construction method makes them virtually impossible to construct. It goes without saying that such complicated mirror systems would lead to far more exciting symmetrical image patterns and is therefore highly desirable. Thus there is a need for an improved methodology for fabricating mirror systems for the kaleidoscopes which can handle the construction for more complicated mirror systems.
For the kaleidoscope cited as an example in the present discussion, the mirror system is but one of many components that together make up the kaleidoscope. While kaleidoscopes may vary greatly in appearance and quality, there are four primary elements in any design. They are 1) the eye piece, 2) the body, 3) the mirror system and 4) the object chamber.
In a conventional way of making a kaleidoscope, each of the above elements is individually constructed and then they have to be painstakingly assembled together. Since the mirror system is the soul of the kaleidoscope, it is highly desirable in terms of time and ease of assembly to have it constructed with built-in or integrated features so as to be able to easily accommodate the other three elements in the making of the kaleidoscope. Clearly the manual method of making the mirror system for the kaleidoscope cannot fulfill this desirable feat. Thus there exists a further need for an improved kaleidoscope mirror system fabrication methodology that can provide this desirable feature of overall system integration for the construction of the kaleidoscope.